WARNING: The following article contains spoilers for Uncanny X-Men #21, by Matthew Rosenberg, Salvador Larroca, Guru-eFX and Joe Caramagna, on sale now.
One of the darkest periods in X-Men history is almost over, but it's not quite done yet. With the majority of the X-Men wrapped up in the "Age of X-Man," a recently revived Cyclops and Wolverine have led a ragtag team of X-Men in a world where mutants have been driven to the brink of extinction.
Thanks to the mutant-hating General Callahan, a vaccine has seemingly depowered a generation of mutants as a vicious new breed of Sentinels hunts down the remnants of mutantkind. As the X-Men have suffered numerous casualties, they've teamed-up with some familiar and forgotten foes to save what's left of the mutant race.
Despite the team's best efforts, another pair of X-Men, Velocidad and Banshee, both seemingly died in Uncanny X-Men #21.
While Banshee died in battle, Velocidad's own super-speed powers were tragically turned against him and left him in such a sorry state that Wolverine ultimately had to put him out of his misery.
While Velocidad has considerable super-speed powers, the teen mutant grows older whenever he uses them. Although Gabriel Cohuelo was one of the teenage heroes of the Generation Hope team a few years ago, he appears to be in late middle-age when Logan encountered him a few months ago, since he had been relying on his powers to help the sewer-dwelling Morlocks survive.
When Logan stumbles upon Velocidad in this issue, he discovers that the speedster's powers are being used for a far more sinister purpose. After being forcibly bonded to a piece of Warlock, a techno-organic Technarch alien, by General Callahan, Velocidad had been forced to use his powers to grow new Warlock specimens at super-speed.
When Logan found Velocidad, the once-young hero was in a withered, elderly body on the brink of death. After Gabriel says that he wouldn't survive a rescue attempt, Logan ends his suffering.
Callahan and the Office of National Emergency used those Warlocks to create a vicious new breed of Sentinels that fused the techno-organic alien with mutant-hunting machines. Although they originally used mutants who had been infected with the Technarch-based Transmode virus as unwilling pilots, it's unclear if these Sentinels still rely on mutant pilots.
Regardless of how they were being operated, these Technarch Sentinels still proved to be effective, deadly weapons in combat. When Cyclops and the X-Men make their last stand at the Hellfire Club's headquarters, the veteran X-Man Banshee dies after one of the Sentinels captures him and explodes.
Banshee was part of the second generation of X-Men who joined the team alongside iconic characters like Storm, Nightcrawler and Wolverine. Although Sean Cassidy was never quite as famous as his teammates, the mutant with a supersonic scream was a steady part of the X-Men's world for decades, and he trained the young mutants of Generation X into the competent adult heroes they are today.
However, Banshee hasn't quite been the same since he died in a plane crash in 2006's X-Men: Deadly Genesis storyline. Like several other X-Men, Banshee was resurrected by the villain Apocalypse and turned into one of his evil Horsemen of Apocalypse. After the X-Men took Banshee into their custody, Beast said that it would take years to undo Apocalypse's mental programming in 2014.
When Banshee returned to semi-active duty earlier this year, he confirmed Beast's claims by essentially operating as an often silent, emotionless zombie in the months leading up to his death.
Although Banshee and Velocidad were the only casualties in this issue, a few other X-Men either lost control of their abilities or lost their powers altogether. General Callahan's forces seemingly depowered the young mutant healer Triage, and he unleashed the dark mystical beast that lies inside Magik. Subsequently, the monstrous Magik then destroyed the Crimson Gem of Cyttorak that gives the Juggernaut his power.
While all of these losses have painted the X-Men into an incredibly tight corner, Emma Frost's plan to make the rest of the Marvel Universe forget about mutants was seemingly successful. With House of X and Powers of X set to kick off a new era for the X-Men later this month, it won't take much longer to figure out how much staying power the X-Men's recent losses will ultimately have.